Donald J. Trump has the good fortune of taking office as the economy is finally recovering from the 2008 crisis. For Democrats, the bad news is that just as Barack Obama got tarred by the struggling economy that he inherited from George W. Bush, Trump will get credit for the good economy that he inherits from Obama—growth in the last quarter of 3.5 percent, unemployment of 4.6 percent (a level not seen for nine years), and 16 million jobs added since the recovery began.

All this will be good for Trump, if he doesn’t mess it up. And that’s the rub: there is a good chance he will. His policies make it almost inevitable. The president-elect seems to believe that he can make the economy grow at 4 percent annually, as promised, while at the same time massively bringing down the trade and fiscal deficits, if not turning them into surpluses. But the laws of economics don’t bend to political rhetoric, and there are some surprises in store for the new president.

First, let’s take a look at what seems to be Trump’s core economic strategy. To the extent that a strategy can be discerned, it involves a big tax cut for the rich, an infrastructure program driven by tax credits, increased military spending, browbeating firms not to move jobs abroad, a 45 percent tariff on goods from China, and the repeal of the Dodd-Frank legislation and other financial and environmental regulations. For those of us old enough to remember Ronald Reagan, it’s largely another dose of Reaganomics: the notion of incentivizing the economy through lower taxes while simultaneously liberalizing the economy so that entrepreneurs can get down to the task of making it strong. Indeed, the growth should be so strong that, in theory, tax revenues would increase and even those at the bottom, who got little direct benefit from tax cuts, would be much better off than they otherwise would have been.

Well, for Reagan, things didn’t quite go as planned. The deficit soared, growth slowed, inequality grew, those in the middle saw their incomes stagnate, and those at the bottom saw their incomes fall. The economy began its rapid deindustrialization, but nothing was done to help those whose jobs were destroyed. Thus was born the “displaced middle”—the group of angry middle-aged white men who seem to have been central to Trump’s campaign.

Video: What’s Next For Donald Trump?

As the liberalization agenda continued after Reagan, the economy became exposed to increasing risks, facing its first financial crisis in more than a half century, in 1989, and the worst crisis in three quarters of a century, in 2008. Remarkably, after having suffered so much from this agenda—and with those in the middle having built up understandable anger—the country decided in 2016 to double down on a failed strategy.

Trump has been criticized by mainstream Republicans for not really being one of them. But he is definitely one of them when it comes to the central palliative for any ill befalling the country: a tax cut for the rich. Indeed, his proposed cut goes further than the tax cuts that others have proposed, with fully half the benefits flowing to the top 1 percent of Americans. Trump’s corporate tax reform has one thing to say for itself: it would end the perversion of the current system, which encourages multi-nationals to park their money abroad. But it does this at an enormous price: lowering the tax on the repatriated funds to some 10 percent, perhaps less—a tax giveaway of at least half a trillion dollars. And one thing we can be sure of: reducing taxes on past investments provides no beneficial future incentive.

The laws of normal economics dictate that lower taxes combined with increased spending will lead to bigger deficits. Trump criticized Obama’s deficits. How does one square the circle? Trump has some spending cuts in mind, but there will be significant spending increases, too—for instance, on the military. Privatization of Medicare will also be expensive, so spending there will increase as well, even if benefits received by the elderly decrease. And because federal-government employment has been repeatedly trimmed—as a percentage of the population, it’s the lowest it has been in at least 100 years—there’s not much fat left to cut. Someone has to administer well-loved programs, like Social Security, and someone is going to have to round up all those 11 million immigrants in order to deport them.

George H.W. Bush famously criticized Reagan for his “voodoo economics.” And he was right. But Trump is taking a page out of the same book. Somehow, this time, tax cuts and spending increases will so stimulate the economy that tax revenues will grow. In fact, Trump is as likely to be disappointed as Reagan was. People forget, but Reagan was forced to reverse and revise his 1981 tax cuts twice—in 1982 and 1986.

America has a major infrastructure deficit. Both Hillary Clinton and Trump recognized this. Trump’s plans for $1 trillion in infrastructure investment seem grandiose, but as with so much of Trump’s program, there is less here than meets the eye. His infrastructure program is supposed to be financed out of an 82 percent tax credit to hedge funds and others who undertake this investment. But unless one is willing to be patient—to wait three to six years—one has to rely on the long discredited “shovel ready” projects, which may create jobs willy-nilly, but won’t constitute the strategic infrastructure revolution the country needs.

Hedge funds are not noted for their long-term thinking—for them, a quarter is an eternity. Their goal will be to turn a quick buck on the government’s magnanimous offer before Washington wakes up. Here’s what they’ll likely do: they’ll try to privatize whatever public assets can be sold. Of course, from a societal point of view, this is not investment—it’s just changing ownership and control of assets. With the federal government paying 85 cents of every dollar spent in privatization, we can expect a gold rush. Ordinary citizens will pay twice for this gift to the hedge funds: first through the cost of the tax credits, and second through the tolls and fees that private owners will charge to recuperate their “investment.” This is a particularly foolish time to engage in such tax shenanigans, because government can borrow at close to zero interest rates. And it’s not as if the hedge funds have any experience in building and managing infrastructure. The history of such privatizations is disastrous: large numbers of them have failed within a few years, after the funds have taken out their money.

To see how the game is played, at our expense, let’s assume that a trillion dollars actually goes to new investment (an unlikely assumption). If the government itself had made the investment, the annual cost to the taxpayer would be $20 billion, assuming a 2 percent interest rate. Now assume that hedge funds borrow 80 percent, adding in $200 billion of their own money. But with the 82 percent tax credit, the Treasury is out $820 billion.

Note the Houdini arithmetic: the hedge funds only had to put up $200 billion, but they get a check from the Treasury for $820 billion. Trump doesn’t seem to understand that a tax credit is a form of government spending. That’s why we call such spending “tax expenditures.” His trillion dollars for “infrastructure spending” will not translate into a trillion dollars of new infrastructure. It will translate into a trillion dollars of additional deficit.

Trump has criticized the Federal Reserve for maintaining interest rates that are too low. Many members of the Fed have also been itching to raise interest rates. Some (joined by gold bugs and inflation hawks on Trump’s team) see inflation around the corner, given the buildup in the Fed’s balance sheet. Some worry about the distortion in financial markets, especially as irrational markets seem to price risk too low when interest rates get low. Some, worried that we have not had a recession for eight years (far longer than the typical period), want to “re-arm” the Fed so that it has some ammunition when the next one occurs. Trump has two appointments to make to the Fed, and if he chooses those inclined to his views, and replaces Janet Yellen when her term ends, in 2018, then interest-rate hikes and monetary tightening seem inevitable. But these actions will almost surely slow down the economy. There’s a good chance that monetary tightening will more than offset any stimulus that comes from tax cuts or new spending.

That’s because the fiscal stimulus is likely to be weak. As noted, much of the infrastructure spending won’t go to new infrastructure, but to privatization of existing infrastructure. Much of the money from that, as well as from the tax cuts, will go to the 1 percent, who spend a much smaller fraction of their income than those at the bottom.

There’s one more reason that the economy will be weak: contrary to what Trump wants or intends, the trade deficit will increase. Here’s a bit of economics that likely goes beyond Trump: whenever a country invests more than it saves, there must be an inflow of capital to finance the deficit; and that inflow of capital must be equal to the country’s trade deficit. Economists differ on lots of things, but not on what I’ve just written; these are truisms. So again, what matters is not political rhetoric, but a close examination of the underlying forces.

Trump claims that his program will stimulate national investment. As I’ve explained, I think he’s exaggerated the extent of new infrastructure. If history is a guide, little of the multi-national money coming back, under an amnesty, will wind up in investment, despite whatever promises are made. And higher interest rates and tighter monetary policy are likely to dampen investment, especially among small- and medium-size enterprises, the source of job creation in any economy.

But assume that Trump is partially correct: there will be an increase in national investment. At the same time, national savings are almost surely going down, as the deficit soars from the tax cuts. That means that the trade deficit will increase. And with the increase in imports exceeding exports, G.D.P. will be depressed. Worse still, the very group that Trump promised to help will be among the biggest losers, as America continues on its path of deindustrialization.

How, one might ask, is this possible, given Trump’s rhetoric, his determination to move against China with a 45 percent tariff? There’s a global macroeconomic variable that Trump left out of his calculus, and that’s America’s exchange rate—not just with China, but with the entire world. If America’s exchange rate increases, our exports become more expensive, and imports become cheaper—Italian designer clothing for the 1 percent and Indian and Bangladeshi clothing for the 99 percent.

Higher interest rates normally result in a higher exchange rate. But what happens if Trump does build his wall with Mexico, repeals NAFTA, imposes 45 percent tariffs against China, and labels China a foreign-exchange-rate manipulator? One of his advisers should have told him that China has been intervening in its exchange rate to prevent it from falling. If China stopped intervening, its exchange rate would fall—and our imports from China would increase. If it reduced restrictions on its citizens investing abroad, it would fall even more. If Trump imposes new tariffs on China, production of clothing and textiles won’t shift back to the U.S.; it will just move to elsewhere in the developing world. A few hi-tech companies might start producing goods in the U.S., but the sad news is that the jobs will be few and they will be hi-tech—not the jobs promised for the dislocated workers of the Rust Belt. And again, Trump will be foiled by the exchange rate: the higher tariff will result in a depreciation in China’s exchange rate, partially undoing any hoped-for benefits.

If Trump builds his new wall with Mexico, America’s car manufacturers will find themselves in an even tougher place than they are now. Without cheap car parts, they become un-competitive, both at home and abroad. The net result may be a loss of jobs, not more jobs. This is just another example of the jolt awaiting Trump: the world is a more complicated place than his rhetoric allows.

The real danger, however, is that Trump is edging America towards a trade war, a war in which we—and the rest of the world—are all likely to be losers. One of the oldest principles in economics is that of comparative advantage—if each country produces the goods in which they have a comparative advantage, each country will be better off. During the past few decades there was a bipartisan failure in not recognizing that even if the country as a whole is benefitting from trade, some groups may lose out—but the fault lies especially with the Republicans, who resisted any form of assistance to those whose jobs were lost as a result. That said, cutting off trade will result in a weakening of overall G.D.P.

But matters are worse: markets on their own are not good at making smooth adjustments, and learning to live without imports, or to live with much higher prices for imports, will not be easy. More jobs will be lost as the country loses comparative advantage across a wide swath of products. Without access to competitive imports, our exports themselves can’t compete. American workers will again lose twice: first because of the loss of jobs, and second, because of the higher prices for consumer goods.

American workers may be deceived by Trump’s blustering; and they may trust that our governmental institutions will prevent him from doing anything totally irresponsible. But foreign governments are likely to be less trusting—and less forgiving. They may resort to international laws and agreements that we have signed—and from which we can disengage ourselves only slowly, and at significant cost.

For instance, the United States pushed other countries to agree to a provision in trade agreements calling for “countervailing duties”: if a country provides a subsidy to a firm—either directly or indirectly, through the tax system—then any of our trading partners can impose an offsetting “duty” or tariff. Providing a subsidy was precisely what Trump did with his deal to keep Carrier/United Technologies deals in Indiana. That is what the U.S. did with the entire banking system, in the form of a massive bailout. It is what Washington did with the auto industry. Other countries have so far looked the other way. But if the U.S. starts playing “tough,” so can they. In fact, the U.S. has been brought before trade tribunals on charges of violating trade agreements 129 times in the past 20 years. But Trump promises to usher in a new era—not in fighting for our rights, but in violating international trade law.

Here’s another dirty secret about U.S. trade negotiations that nobody seems to have told Trump. Our trade agreements are unsatisfactory not because our negotiators failed to get what they wanted, but because they succeeded: the trade agreements were written by and for corporate interests. The intellectual-property provisions, which promise to increase drug prices and discourage innovation by small- and medium-size firms, were pushed by Big Pharma. Generic drugs, American consumers, and global science have been among the losers. And again, someone will have to break the news to Trump that among the strongest supporters of these provisions have been Republican senators. Either way, Trump is in for trouble: either he breaks with those whom he promised to bring in a new era of trade deals, or he breaks with the powerful special interests who underwrite his own party. The real conflict is not between workers in the U.S. and those elsewhere; it’s between workers everywhere and corporate interests everywhere.

Donald Trump’s success has been based on doing deals—deals that are, for the most part, zero-sum games. He does well if he can get his counter-party to agree to a lower price; he does even better if he finds some way of cheating the counter-party. Trust, fairness, honesty, or a sense of equity don’t rank high in this calculus. Presiding over a vast national economy is an order of magnitude more complex than just making deals. For one thing, it requires understanding that a national economy is not an end in itself—it’s a means to something else.

The prospect ahead is that Trump will not be merely a zero-sum president. He will be a negative-sum president. And if the billionaires insist on getting an ever larger slice of a diminished pie, it will mean that the crumbs left over for the rest become smaller and smaller.

Mitt Romney

The O.G. Never Trumper, Romney effectively renounced his past denunciations of the president-elect, whom he had previously called a “con man,” when Trump began publicly courting him for secretary of state. (He did not get the job.)

Photo: Digital Colorization by Ben Park; From Getty Images.

Chris Christie

During his presidential campaign, the New Jersey governor called Trump a “thin-skinned,” “13-year-old,” whose ideas “made no sense,” so it was quite the surprise to see Christie standing shell-shocked at Trump’s side, weeks after he dropped out, upon giving him his hearty endorsement.

Photo: Digital Colorization by Ben Park; From Getty Images.

Ted Cruz

After Trump insulted his wife’s looks, the Texas senator responded by all-but calling his primary opponent a ratf***er and refused to endorse him during a speech at the Republican National Convention. But months later, not only did he urge his voters to pull the lever for Trump, he was spotted morosely phone-banking in front of his former enemy’s campaign signage.

Photo: Digital Colorization by Ben Park.

Reince Priebus

A long time ago, in the year 2016, the R.N.C. chairman threw everything he could to prevent Trump from becoming the party’s nominee. Days after Trump won, Reince stood by his side as his chief of staff, possibly getting the least humiliating outcome for an erstwhile Trump foe.

Photo: Digital Colorization by Ben Park; From Getty Images.

Paul Ryan

The House Speaker spent months trying to maintain a safe distance from Trump, condemning his statements (even as he declined to renounce him) and at one point canceling a rally appearance with Trump after his past p****-grabbing comments came to light. Flash-forward two months, and Ryan was praising Trump in front of a cheering crowd in Wisconsin, thanking him for clinching the first Republican presidential win in the state in decades.

Photo: Digital Colorization by Ben Park; From Getty Images.

Jason Chaffetz

“I’m out. I can no longer in good conscience endorse this person for president,” the Utah congressman declared days after the Access Hollywood tapes leaked, calling Trump’s comments “some of the most abhorrent and offensive comments that you can possibly imagine.” It took Chaffetz only 19 days to flip back to Trump.

Photo: Digital Colorization by Ben Park; From Getty Images.

Ben Carson

When Trump compared him to a child molester, the soft-spoken neurosurgeon responded that he would “pray for him,” the Carson equivalent of a sick burn. But after Carson wandered onstage at Mar-a-Lago to give his endorsement, he immediately transformed into one of Trump’s most consistently confusing surrogates.

Photo: Digital Colorization by Ben Park; From Getty Images.

Mitt Romney

The O.G. Never Trumper, Romney effectively renounced his past denunciations of the president-elect, whom he had previously called a “con man,” when Trump began publicly courting him for secretary of state. (He did not get the job.)

Digital Colorization by Ben Park; From Getty Images.

Chris Christie

During his presidential campaign, the New Jersey governor called Trump a “thin-skinned,” “13-year-old,” whose ideas “made no sense,” so it was quite the surprise to see Christie standing shell-shocked at Trump’s side, weeks after he dropped out, upon giving him his hearty endorsement.

Digital Colorization by Ben Park; From Getty Images.

Ted Cruz

After Trump insulted his wife’s looks, the Texas senator responded by all-but calling his primary opponent a ratf***er and refused to endorse him during a speech at the Republican National Convention. But months later, not only did he urge his voters to pull the lever for Trump, he was spotted morosely phone-banking in front of his former enemy’s campaign signage.

Digital Colorization by Ben Park.

Reince Priebus

A long time ago, in the year 2016, the R.N.C. chairman threw everything he could to prevent Trump from becoming the party’s nominee. Days after Trump won, Reince stood by his side as his chief of staff, possibly getting the least humiliating outcome for an erstwhile Trump foe.

Digital Colorization by Ben Park; From Getty Images.

Marco Rubio

The Florida senator, who Trump ruthlessly mocked as “little” and “sweaty” throughout the primary race, so despised his antagonist that he made the ill-fated decision to hit back in kind, mocking Trump’s makeup and hand size. After he dropped out, it took several months for him to embrace Trump, though he could not bring himself to appear at the R.N.C. in person to make the endorsement, sending in a video instead.

Digital Colorization by Ben Park; From PBS.

Paul Ryan

The House Speaker spent months trying to maintain a safe distance from Trump, condemning his statements (even as he declined to renounce him) and at one point canceling a rally appearance with Trump after his past p****-grabbing comments came to light. Flash-forward two months, and Ryan was praising Trump in front of a cheering crowd in Wisconsin, thanking him for clinching the first Republican presidential win in the state in decades.

Digital Colorization by Ben Park; From Getty Images.

Jason Chaffetz

“I’m out. I can no longer in good conscience endorse this person for president,” the Utah congressman declared days after the Access Hollywood tapes leaked, calling Trump’s comments “some of the most abhorrent and offensive comments that you can possibly imagine.” It took Chaffetz only 19 days to flip back to Trump.

Digital Colorization by Ben Park; From Getty Images.

Ben Carson

When Trump compared him to a child molester, the soft-spoken neurosurgeon responded that he would “pray for him,” the Carson equivalent of a sick burn. But after Carson wandered onstage at Mar-a-Lago to give his endorsement, he immediately transformed into one of Trump’s most consistently confusing surrogates.